Play and hypothesis testing: From a note to my research group

I do not believe in the model that science advances by testing hypotheses. I think that people play and then stumble across something interesting and then later repose what they stumbled across as a hypothesis to be tested.

I think we need to do two things simultaneously:

  1. We need to have fun and be playful and work on things that seem interesting even if there is no obvious high impact paper to come out of it.
  1. We need to focus on writing high impact papers that make important novel contributions.

Most scientists essentially rewrite the same paper over and over again throughout there careers, as they slowly drift off into irrelevancy.  This is what happens when people just go on just treating aspects of problems not treated in their previous papers. To remain vital, we must address new problems.

So, the questions are:

A. What are avenues of play likely to be fruitful in leading to interesting, relatively unexplored territory?

B. What are potential important high impact papers that we can be working on now?

Reversal of radiocarbon flux into the ocean

Radiocarbon is produced naturally in the stratosphere when cosmic rays strike atmospheric nitrogen. Most of it decays in the deep ocean. The natural pattern is for radiocarbon to be produced in the stratosphere and mix through the atmosphere. It is then absorbed by the ocean where it decays. So, the net flow throughout most of this planet’s history is for radiocarbon to go from atmosphere to ocean.

This natural pattern is disturbed by two different sorts of human activities — both disturbing in other ways.

First, humans tested many nuclear weapons in the atmosphere mostly in the 1960’s and this nuclear weapons test more-or-less doubled the amount of radiocarbon in the atmosphere.

Second, humans have been burning a lot of fossil fuel. This ancient carbon is devoid of radiocarbon.

As the CO2 emitted by humans acidifies the ocean, this acidification tends to drive radiocarbon out of the ocean.

Thus, nuclear weapons tests tend to drive more radiocarbon into the ocean and fossil-fuel emissions tends to drive radiocarbon out of the ocean.

In a 1998 paper (Caldeira et al., 1998; http://onlinelibrary.wiley.com/doi/10.1029/1998GL900010/abstract), we wrote “we, predict that atmospheic 14C content will reach a minimum and start to increase within the next few years if fossil fuel burning continues according to a ‘business-as-usual’ even though fossil fuels are devoid of 14C.”  That is, we predicted that the effect of fossil fuel burning would start to overwhelm the effect of the nuclear weapons tests.

If you look carefully at a figure in the supplemental material to a recent paper published in PNAS (Graven, 2015; http://www.pnas.org/content/early/2015/07/15/1504467112), in supplementary Figure S1 panel a, you can see that atmospheric radiocarbon content indeed started increasing at around that time, suggesting that our understanding of global carbon cycle functioning is largely accurate.

This is happening because stratospheric radiocarbon production is now exceeding the rate of ocean uptake of atmospheric radiocarbon.

From the perspective of confirmation of model predictions, this is heartwarming to see. It is nice to make a model prediction and see it later confirmed by observational data. From the perspective of the Earth system, it is of course a disturbing result.

In her recent paper, Graven emphasizes how adding all of this ancient carbon to the atmosphere is making the atmosphere look old from a radiocarbon perspective, which will have obvious implications for future efforts to use radiocarbon to date samples. Plants grow by getting their carbon from the atmosphere. If we add a lot of ancient carbon to the atmosphere, we make modern wood look ancient.

I find it remarkable that, as we pointed out in our 1998 paper, sometime around mid-century, ocean acidification from our fossil-fuel CO2 will cause radiocarbon to stream out of the ocean into the atmosphere, reversing the natural direction of flow.

For billions of years, the radiocarbon flow has been going from atmosphere to ocean. There is no time known in Earth history when this flow has been reversed. If we continue current trends in fossil fuel combustion, sometime around mid century, this flow will reverse and radiocarbon will stream out of the ocean into the atmosphere. This may not have huge practical implications outside of radiocarbon dating and similar pursuits, but this reversal acts as a reminder of the magnitude of humanity’s impact on the environment, and how geologically unusual our modern era is.

It is great to see Heather Graven extend our work and show how important fossil fuel burning will be for future efforts to use radiocarbon to estimate the age of archaeological materials.  Our earlier paper was more philosophical and less practical, and was largely ignored. (It has only been cited 9 times since being published 17 years ago.) I thought the fact that we will be reversing the direction of radiocarbon flow that has persisted for billions of years would be of broad interest and receive widespread attention. It did not. I am grateful to Heather Graven for giving our work some attention and extending it in new directions.

Do open discussion journals provide a service to the scientific community?

The open “discussion” journals favored by the European Geophysical Union (EGU), including Atmospheric Chemistry and Physics Discussions (ACPD), may be doing the scientific community a disservice.

For those not initiated into the ways of these journals, scientists submit manuscripts to Atmospheric Chemistry and Physics Discussions where they are published without peer review, and then later if successfully peer reviewed, a modified version appears in the regular journal Atmospheric Chemistry and Physics (ACP).

This produces at least two versions of every paper: a non-peer-reviewed draft and and a final peer-reviewed version. The continued circulation of the non-peer-reviewed draft can act as a kind of pollution of the scientific literature, as it is often unclear to the uninitiated that papers published in EGU “Discussions” journals are not peer reviewed.

One of the key contributions of the editorial and peer-review process provided by journals is the vetting of the scientific content both for importance and quality. There is way too much stuff being written to read everything, and the editorial process at a high-quality journal is supposed to help provide a filter and direct scientists to important, high-quality, papers.

It is a fiction to believe that busy scientists have the time to review a panoply of manuscripts that they are not specifically tasked with reviewing. Journal editors know how hard it often is to obtain thorough reviews of submitted manuscripts.

There may be other models that would allow volunteer reviewing without expanding the reservoir of grey literature. For example, journals could list titles of papers sent out to review, and volunteer would-be reviewers could contact the journal and ask to be made a reviewer.

By publishing papers that are not peer reviewed, EGU journals such as ACPD are contributing to the noise of science, when the role of the editorial process should be to help readers find the rare nuggets of important high quality signal amid the abundance of excess noise.

[Note: This post was prompted by Andy Revkin’s piece of DotEarth: http://mobile.nytimes.com/blogs/dotearth/2015/07/23/whiplash-warning-when-climate-science-is-publicized-before-peer-review-and-publication/ ]

What’s one initiative, project, or change in human behavior that’s crucial for fixing our planet?

On 13 March 2015, I got an email from Ryan Grimm, managing editor of Vice magazine, asking me:

What’s one initiative, project, or change in human behavior that’s crucial for fixing our planet? It can be something that’s currently underway, poorly under-funded, stalled in government, or highly improbable and never going to happen. It can be an idea no one talks about but should, or something that you just thought of today that you’re sure is a genius plan. In short, what’s one specific thing humans can do to help reverse the harm we’ve done?

We then had an email exchange which I thought was a discussion about what I would write were I to write something. This discussion tailed off, so I assumed that they decided my ‘genius plan’ was insufficiently genius.

Thus, I was surprised (and pleased) a few weeks later to get a pdf of a layout for the magazine with an edited form of our email discussion. I requested that one sentence be added to make the first paragraph parallel what follows.

This is what resulted: http://www.vice.com/read/sos-0000653-v22n5

big-bend

MAKE PEOPLE BETTER
Ken Caldeira, climate scientist

The most important thing that humans can do right now is initiate a major research program to understand how we can develop social systems that encourage people to put aside short-term personal gain in favor of long-term social and environmental benefits. Or perhaps we can develop social systems that align short-term self-interest with long-term societal and environmental interests.

In some countries such as Italy, when a bus arrives, people clamor around the entrance struggling to be among the first to get in. In other countries such as the United Kingdom, people form an orderly queue waiting for the bus. What forces cause people to stand at the end of the queue? How does a country transform from one that does not queue to one that does?

One possibility is that people recognize that it is in their long-term self-interest to live in a society where everyone queues, so they queue to help create or sustain that society. It might also be that people get on the end of the queue because their fellow citizens would abuse them if they attempted to cut in front. In other words, negative consequences result in the maintenance of a system that serves the public good.

Our environmental (and political) problems largely stem from people acting in their own narrow short-term self-interest instead of the general long-term public good. The central question facing us is how to transform societies composed of self-interested people into societies composed of people who act to further the public good.

Ken Caldeira is an atmospheric scientist in the Carnegie Institution for Science’s Department of Global Ecology.

Advice for college undergraduates …

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photo: nbcnews.com

Someone wrote me asking for advice for her son who would soon be entering college as an undergraduate to pursue a scientific career. This is how I responded:

My advice is largely the same regardless of the specific career goal.

1. Early in your career / life, you do not know where you might end up, so key is to keep options open.

2. In almost any career with a technical component, key skills include being able to read well, write well, speak publicly well, do math well, think clearly, communicate well with graphics, work with other people, finish projects, etc. In terms of knowledge, there should be a basic foundation in physics, chemistry, and biology. I would focus on getting this broad grounding rather than in developing specialized knowledge.

Key here is the ability to think clearly, have basic quantitative skills, be able to present your ideas well both in written and verbal form, and be able to bring to completion projects that you start. Almost everything else can be learned at a later date. Graduate school is really the place for specialization. Undergraduate education is the foundation.

3. People do best doing what they love. I would advise my son (and I have!) to pursue their dreams with passion. When I was in high school, I could get by being a little lazy because I was smart, and I thought talent could substitute for hard work. To be competitive at an international level, you have to be both talented and hardworking. Your competition will be both. Being slightly obsessive is a positive characteristic professionally.

4. I would show my son this graduation speech, because I think Tim Minchin pretty much nailed it with regard to advice for young people: http://www.timminchin.com/2013/09/25/occasional-address/

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Conspiracy trails …

manycontrails

photo: http://www.co2offsetresearch.org/aviation/Contrails.html

I get a fair amount of emails from people who believe in the ‘chemtrails’ conspiracy theory. Typically, these are people deep into conspiracy theories who also believe that the CIA was responsible for crashing planes into the World Trade Center on 9/11, think the CIA was behind the JFK assassination, and I bet a significant fraction of them think that we never really landed on the moon.  The best predictor of believing in ‘conspiracy trails’ is believing in other conspiracy theories.

Many of these people imagine that I am somehow commanding a fleet of airplanes in my spare time or that I am in some other way masterminding some secret nefarious government conspiracy to poison them or change their climate.

I feel sorry for these people because they have no real way of finding out the truth for themselves, they trust people who believe false things, and they (and we) cannot rely on our government to tell us the truth.

Very few of our beliefs are based on first-hand observation. We hold most of our beliefs because people we trust told us something that was consistent with our prior beliefs. If we trust the wrong people, we can end up with false beliefs.

One of the key facts that conspiracy-trail-believers miss is that scientists, if they could prove that such an atmospheric spraying program exists, would get a very high profile publication out of it in a major journal, and it would be very helpful to their careers. If there were activities going on at the scale suggested by the true believers, it would be obvious to atmospheric scientists. The idea that you can keep every competent atmospheric scientist mum about ‘conspiracy trails’ strains credulity.

Human psychology works in ways that are not entirely consistent with formal deductive logic. For example, if you believe that God creates beautiful flowers, every time you see a beautiful flower, you take that as evidence in support of the existence of God. Similarly, if you believe that contrails are produced by a secret nefarious government plot against humanity, every time you see a contrail, you take this as evidence for a secret nefarious government plot against humanity. The belief is self-reinforcing.

Here is a typical email that I have written in response to people who accuse me of masterminding such plots. I am sure it would be wiser not to respond to these people. But some conspiracy-trail believers are not deep into conspiracy theories themselves but merely trust someone who is deep into conspiracy theories. These are the people I am trying to reach.


Dear ________ ,

You have have apparently been misinformed by trash you read on the internet.  It would be good if you would find out the truth before making insulting and offensive accusations.

You are looking at ordinary contrails and letting yourself succumb to paranoid conspiracy theories.  Are there other conspiracy theories that you believe in? It is said that the best predictor of believing in a conspiracy theory is already believing another conspiracy theory.  Who do you think killed JFK? Who masterminded 9/11?

Please do not be one of these people with no scientific literacy and who believes stupid stuff they read on the internet.

Are all of these contrails experts wrong about contrails?  http://scholar.google.com/scholar?hl=en&q=persistent+contrails  Why aren’t real scientists who study contrails seeing anything unusual?

Why do people studying atmospheric deposition of aluminum not say anything about Chemtrails? http://scholar.google.com/scholar?q=atmospheric+deposition+aluminum  Could it be that there are no Chemtrails that could cause increases in atmospheric deposition?

What some people think of as Chemtrails are just ordinary contrails. Check out this video, for example:  https://www.youtube.com/watch?v=X72uACIN_00  Or this web site: http://contrailscience.com/

Barium and other chemicals are commonly released into the environment. For example, take a look at this:

http://www.inchem.org/documents/ehc/ehc/ehc107.htm

Anthropogenic sources of barium are primarily indus- trial. Emissions may result from mining, refining, or processing of barium minerals and manufacture of barium products. Barium is also discharged in waste water from metallurgical and industrial processes. Deposition on soil may result from man’s activities, including the disposal of fly ash and primary and secondary sludge in landfill. It was estimated that in 1976, mining and processing of barite ore in the USA released approximately 3200 tonnes of particulates into the air, and fugitive dusts from the use of barite in oil drilling and oil-related industries accounted for approximately 100 tonnes of particulates. In 1972, the barium chemical industry in the USA released an estimated 1200 tonnes of particulates into the atmosphere.

So, there are something like 4000 tons of barium-containing compounds released into the air over the US each year by industry. You don’t need to invoke Chemtrails to explain barium deposition.

Do you really think Dick Cheney cared enough about climate change to run a secret program to try to protect us from climate damage?

Our government asserts the right to kill Americans secretly without judicial review, so I am under no illusions that our government is willing to do terrible things in secret. Furthermore, our government has lied to us about kidnapping and torturing people and many other things. So, I understand when people think the government is doing terrible things again and lying to us about it. That is often a reasonable first guess at an explanation.

Unfortunately, in this case I think this reasonable first guess is wrong. There is no good evidence that our government is running a secret spraying program and lying to us about it.

Best,

Ken

PS. To learn more about me and my views, you can check these out:

SF Chronicle: http://www.sfchronicle.com/science/article/Warning-from-climate-science-front-lines-4569221.php?t=4f3395796547b02379

ClimateProgress:

http://thinkprogress.org/climate/2012/04/15/462803/caldeira-only-ethical-path-is-to-stop-using-the-atmosphere-as-a-waste-dump-for-greenhouse-gas-pollution/

http://thinkprogress.org/climate/2013/09/30/2699121/real-budget-crisis-co2/

http://thinkprogress.org/climate/2012/03/12/442484/ken-caldeira-natural-gas-is-bridge-to-a-world-with-high-co2-levels-deployment-is-to-rampd-as-elephant-to-mouse/

NPR All Things Considered:  http://www.npr.org/2013/04/22/176344300/this-scientist-aims-high-to-save-the-worlds-coral-reefs  (broadcast 22 April but web page went up on 5 April)

I tell the truth about geoengineering. Have a look at this: http://www.theeuropean-magazine.com/373-caldeira-ken/372-climate-change-and-geo-engineering

Fast, cheap and easy … and very dangerous

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Last week, I got an email from an editor at USA Today. The email said “We’re looking for someone to … argue for geoengineering as a viable means to fight climate change”, continuing “We would need 350 words by 3 PM tomorrow afternoon.”

They said that they couldn’t show me the piece I would be responding to (!), but the main points would be:

— As the NAS panel said, geoengineering is no substitute for reducing greenhouse gas emissions, the root cause of the problem.

— Albedo modification on a global scale could have major unintended consequences.

— Carbon dioxide removal is less problematic but is probably cost prohibitive, particularly if carbon emissions remain untaxed.

— Research should continue into climate intervention only as a last-resort, if-all-else-fails option.

I responded, saying, “OK. The stuff that you are saying is stuff that I largely agree with. Nevertheless, you can argue that the glass is half empty and I can argue that the glass is half full, arguing for the potential benefits.”

They responded, saying, “OK. The more half full, the better.”

So, I set out to write a piece that would be as strong and one-sided as possible, without saying anything that I thought was false. Note that my intent was NOT to present a balanced view, but to argue a side as a lawyer might argue a case.

I gave them about 100 words more than they asked for, and they cut it down to size.

The piece by the USA Today editorial board can be found here:

http://www.usatoday.com/story/opinion/2015/02/15/climate-change-solar-geoengineering-greenhouse-gases-editorials-debates/23465849/

My piece can be found here:

http://www.usatoday.com/story/opinion/2015/02/15/megadrought-climate-change-ken-caldeira-editorials-debates/23465975/

I think what I said is true, but is not balanced.

I wrote an email to a friend about this:


The USA Today piece is a bit too high-pitched for my comfort level. The same thing happened with me writing OpEds for the NY Times

The media outlets want you to be as extreme and outlandish as possible because that sells copy, and they know you want to be published and say that if you are too lukewarm, we will find someone else who will say more provocative things. So you compromise and become a little more strident than you really feel comfortable with because you are an egomaniac who wants the public exposure.

UPDATE 17 FEB 2015

A few people, including my Mom, read what I wrote here the wrong way.

First, let me say that I thought the editorial handling by USA Today was great. When they edited 100 words out of my piece, they did so very professionally and did not attempt to alter my point of view.

Going in, I knew that the balance was to be provided by the two pieces together (my piece and their piece) and that this was not intended as a forum for me to have a full airing of my views but rather, in presenting contrasting views, it was meant to be something that would be both entertaining and informative to the reader.

Their piece was, I thought, good and very professionally and thoughtfully done.

We don’t know what is in other people’s minds. When I write about what I think others want of me, that likely reflects my psychology more than any objective reality. Nobody pushed me into doing anything I didn’t want to do.

My Mom got the impression that I felt somehow mistreated by the USA Today staff.  That couldn’t be further from the truth. I am deeply appreciative of the opportunity they offered me.  I  think the two pieces together present a balanced view.

I told my Mom that she shouldn’t be concerned about me; she should be happy for me that I was given such a wonderful opportunity.

http://www.usatoday.com/story/opinion/2015/02/15/megadrought-climate-change-ken-caldeira-editorials-debates/23465975/

One known way to cool the Earth: Another view

Solar geoengineering could be fast, cheap and easy.

If current trends in greenhouse gas emissions continue, unprecedented megadroughts may plague much of the western USA, and the tropics may get so hot that widespread crop failures and famines become commonplace. There is a chance that climate change will prove truly catastrophic, with people suffering and dying in many parts of the world.

With the Earth in such a fevered state, there will be intense and irresistible pressure for politicians to do something, anything, to cool things off.

People in crisis won’t want to wait decades for carbon dioxide-polluting energy systems to be transformed. And even if emissions of all greenhouse gases were stopped suddenly, the Earth would remain hot for thousands of years. There is basically only one way known to cool the Earth rapidly.

The only thing politicians can do to cause Earth’s climate to cool within their terms in office is to reflect more of the sun’s warming rays back to space. We know this is possible because we have seen volcanoes do it. In 1991, the Mount Pinatubo eruption in the Philippines injected lots of small particles high in the atmosphere, and the next year the Earth cooled, despite the continued rise in atmospheric greenhouse gas concentrations.

A small fleet of airplanes could do what large volcanoes do — create a layer of small particles high in the atmosphere that scatters incoming sunlight back to space. Cooling the Earth this way could be fast, cheap and easy.

With the Earth in a fevered state, the pressure to put on a “solar geoengineering” ice pack could become irresistible, especially if this ice pack could potentially save millions of lives.

It is possible, of course, that sustaining the kind of aerosol layer that circled the Earth in 1991 would just make things worse. We just don’t know. We need to do the research so that if a climate catastrophe does occur, politicians will know whether turning down the heat this way can really save lives and alleviate suffering.

Ignorance is not an option. The cost of not knowing is too large. The ethical path forward is to generate the knowledge now that may be needed to save lives in the future.

Ken Caldeira is a climate scientist with the Carnegie Institution for Science at Stanford.

On Alan Robock’s comments regarding the CIA and climate intervention

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photo: https://www.flickr.com/photos/jamais_cascio/6214330683/

Alan Robock made some speculative comments about the CIA to the Daily Mail.  These comments can be read here: 

http://www.dailymail.co.uk/wires/pa/article-2954051/Chill-factor-CIA-weather-query.html

On the geoengineering google group (https://groups.google.com/forum/#!forum/geoengineering), I responded:


Based on the history of our intelligence agencies’ involvement in secret kidnappings and torture, killing noncombatants with drones, spying on our telecommunications, etc, we can take it as a given that secret US governmental organizations will engage in criminal behavior.

However, we should be entirely clear:

There is absolutely no evidence that any US intelligence agency has any interest in climate intervention for anything other than defense-related informational purposes.

Furthermore, there is no plausible scenario in which climate intervention could be used effectively as a weapon.

So, while I share Alan’s contempt for the criminal behavior of our secretive governmental agencies, I do not think it is helpful to speculate that in this instance, the agencies are looking for new ways that they might inflict suffering on others.


Jamais Cascio (@cascio, http://www.openthefuture.com/) responded:


It’s not a question of whether or not it’s a weapon, it’s a question of whether or not it’s perceived as a threat.

At the Berlin event, I told some of you about the CIA Center for Climate Change and National Security simulation exercise I was asked to do four or five years ago. What started as a climate disruption/storms & droughts & bears scenario evolved (as the China and US teams responded) into a potential SRM scenario. By the final turn, the possible deployment of SRM on one side had been perceived as a real threat to agriculture on the other, and missiles were being put on alert.

Perception trumps objective reality when it comes to national security.

On that note, the CIACCCNS is no longer around, as the Republican house determined that since climate change wasn’t real, the center wasn’t needed. Seriously.

-Jamais Cascio

Conversation is here: https://groups.google.com/forum/#!topic/geoengineering/QQBGQLPHx5M

Email to David Perlman for ‘Megadroughts’ story

Recently, I was contacted by David Perlman of the San Francisco Chronicle to comment on this paper:

Unprecedented 21st century drought risk in the American Southwest and Central Plains
, ,

http://advances.sciencemag.org/content/1/1/e1400082

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The story he produced can be found here: http://www.sfgate.com/science/article/Megadroughts-predicted-to-ravage-the-Southwest-6078504.php

The email I sent to David Perlman in response to his query was:

This study analyzes results from a broad spectrum of climate models and compares them with paleo-climatic data and comes up with some rather startling results.

These model results are the most reliable model results available in the world today. The models have been tested again and again against a wide array of meteorological observations.

If this was one model saying this, it might be a model artifact, but when nearly every model says more-or-less the same thing, you have to pay attention and believe it might be pointing to something real.

I have looked at some of this model output before, but when you look at them as graphs of probability distribution functions it doesn’t really mean very much emotionally.

When you stack these model projections against reconstructions of past climates, the results are so sobering that they have me ready to go out for a drink.

I remember visiting ruins of American Indian civilizations in the desert southwest, places like Mesa Verde, where large civilizations flourished based on an agricultural foundation. It is thought that the rains dried up in year 1276, and a 23-year drought played a major role in causing this civilizations to fail, leaving us with the ruins we see today.

If you look at the chart showing rain in the desert southwest (Figure 1), the drought of 1276 is like a little blip compared to what is in store for us.

As a climate scientist, I sometimes think climate change is something we can just muddle through. I have been concerned about excessive alarmism, thinking that climate change might turn out to be not so bad for the average person after all.  These results have me questioning that complacent attitude. 

It looks like the droughts in store for us later this century will make the droughts that did in the Mesa Verde civilization look like child’s play. 

Another concern is that the droughts we have been experiencing here in California have been much worse than predicted by the climate models.

As a scientist, I cannot say that this California drought is caused by climate change, but as an ordinary human being I can’t help but wonder if climate change is playing an important role.* I can’t help but wonder if the climate models are under-predicting the intensity of this drought and droughts to come.

Perhaps someday, people will wonder why we called this ‘the global warming problem’. People in the future may call this ‘the regional drying problem’.

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*Post Facto Note: A reader wrote to me and complained about this as-a-scientist / as-a-human being dichotomy. I agree that this was not a very good framing.
Things sent or said to journalists are always the quick rough first draft. The irony is that the scientific papers we labor over to get every word right are read by almost nobody. The stuff we say or write off the top of our heads are the most likely to be widely read.
It is a good hypothesis that anthropogenic emissions are contributing to the extreme weather we have been having, but at this time the evidence in support of that hypothesis is not compelling (and at the same time there is absolutely no evidence that the hypothesis is false).

Getting nasty …

Recently, a friend asked if I was going to respond to critiques from a colleague whose name will go unmentioned. My response was:

I find him someone better ignored than engaged.

If I never interact with him again in my life, it will be no loss to me.

Environmental science of climate, carbon, and energy